Vehicle, and method of assisting driving of same

ABSTRACT

A motorcycle is provided with a determining unit for determining the presence of an automotive vehicle on a non-public road area, an antilock brake system, and a selector unit for selecting the antilock brake system to a behavior mode or a non-behavior mode on the basis of the determination made by the deterring unit. The selector unit, in the event that the presence of the automotive vehicle is determined present on the non-public road by the determining unit, enables the antilock brake system to be settable in the behavior mode or the non-behavior mode.

CROSS REFERENCE TO THE RELATED APPLICATION

This application is a continuation application, under 35 U.S.C §111(a)of international patent application No. PCT/JP2014/050220, filed Jan. 9,2014.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to an automotive vehicle that can move ona public road area as well as a non-public road area such as, forexample, an circuit and, also, to a method of assisting the maneuveringof such automotive vehicle.

2. Description of Related Art

Utilization of an antilock brake system in the automotive vehicle suchas, for example, a motorcycle has been well known (for example, thepatent document 1 listed below). The antilock brake system referred toabove is operable to suppress skidding of the automotive vehicle on aroad surface in the event of the occurrence of the vehicle wheel beinglocked, and is one kind of drive assistance devices for assisting themaneuver of the automotive vehicle.

RELATED DOCUMENT Patent Document

Patent Document 1: JP Laid-open Patent Publication No. 2013-028294

On the other hand, when the automotive vehicle is driven on thenon-public road area such as the circuit referred to above, it may occurthat the driver does not desire any drive assistance done by the driveassistance device such as, for example, the antilock brake system. Ithas, however, been found that concurrent provision of the automotivevehicle for use on the public road area and the automotive vehicle foruse on the non-public road area leads to the increase of costs, andremodeling the automotive vehicle for use on the public road area whenrunning on the non-public road area appears inconvenient andinefficient.

SUMMARY OF THE INVENTION

The present invention has been devised in view of the foregoing problemsand inconvenience and is intended to provide an automotive vehicle thatis convenient in running not only on the public road area but also onthe non-public road area with no special remodeling.

In order to achieve the foregoing object, the automotive vehicledesigned in accordance with the present invention includes a determiningunit to determine the presence of the automotive vehicle on a non-publicroad area, a drive assistance device to assist a driving operation of adriver, and a selector unit to select a drive assistance by the driveassistance device from a public road mode to a non-public road mode inthe event that the determining unit determines the presence of theautomotive vehicle on the non-public road area. The drive assistancedevice referred to above is not the one that is directly operated by thedriver, but is used to improve a vehicle operating feeling by performingan assistance control relative to a driving operation by the driver. Thedrive assistance device is, for example, an antilock brake system. Thenon-public road mode includes, for example, reducing the efficacy of theantilock brake system or delaying the antilock determination, and alsoinclude disabling the antilock brake system.

According to the above described construction, the use of the selectorunit is effective to eliminate or relieve the drive assistance byselecting the non-public road mode on the non-public road area.Therefore, an approximate drive operating feeling is realized by meansof an operation by the driver, and an operation desired by the driver isaccomplished. As a result, the convenience of the automotive vehicle canbe increased. Also, other than the non-public road area, selection ofthe non-public road mode is disabled, and an undesirable release of thedrive assistance can be avoided.

In the practice of the present invention, the selector unit ispreferably configured as to be selectable by the driver in a vehicle runenabled condition. According to the construction described above, withno need to dismantle the automotive vehicle, the non-public road modecan be easily selected and, therefore, the convenience can be increased.The selector unit is, for example, a mode changing switch provided on ahandlebar.

In the practice of the present invention, the selector unit preferablyselects the drive assistance device to the public road mode at anoperation start stage at which a vehicle operation is initiated. Theinitiation of the vehicle operation can be detected when, for example,the main switch for starting the automotive vehicle is manipulated.According to this construction, even though at the time the non-publicroad area is operated previously, the drive operation is terminatedwhile in the non-public road mode, the start can be made in the publicroad mode at the time of subsequent drive operation resumption, and,therefore, it is possible to receive the drive assistance.

In the practice of the present invention, the automotive vehicle ispreferably provided with a display unit to display the capability ofselecting the public road mode and the non-public road mode in the eventthat the determining unit determines the automotive vehicle present onthe non-public road area and also to display the non-public road modebeing selected in the event that the non-public road mode is selected.According to this construction, since the status in that the non-publicroad mode is rendered selectable can be affirmed with naked eyes, theconvenience is further increased. Also, when the selection of thenon-public road mode is displayed, the driver can be aroused that theautomotive vehicle is now under the non-public road mode.

Where the display unit is provided as discussed above, the automotivevehicle is further preferably provided with a mode changing switch toselect a driving mode during the run on the public road, in which theselector unit determines the selection of the non-public road mode whenthe mode change switch is operated. According to this construction, theuse of any extra switch for the selector unit can be dispensed with.With a display of the selectability made on the display unit, theswitching of the driving mode during the run on the public road and theswitching of the non-public road mode for the non-public road drivingcan be realized.

In the practice of the present invention, the determining unitpreferably determines the non-public road mode when a protectivecomponent of the automotive vehicle is removed. The protective componentreferred to above is a component that is statutorily required to bemounted on the automotive vehicle, which runs on the public road, inorder to secure safety and includes, for example, gauges including aspeed meter, a warning sound horn, back viewing mirrors, a headlamp,turn indicators, a brake lamp, a tail lamp and so on. According to thisconstruction, when the protective component, which is necessary whenrunning on the public road area but unnecessary when running on thenon-public road area, is removed, the presence on the non-public roadarea can be determined. Therefore, the convenience is further increased.

The drive assistance method of the present invention is a driveassistance method for use in an automotive vehicle that is equipped witha drive assistance device for assisting a drive operation performed by adriver, which method includes a determining step to determine thepresence of the automotive vehicle on a predetermined assistanceselectable area by a determining device, a selecting step to enable adrive assistance mode by the drive assistance device only when thepresence of the automotive vehicle on the assistance selectable area isdetermined by the determining step, and a switching step to change tothe drive assistance mode, selected by the selecting step, to enable thedrive assistance to be accomplished.

According to the construction described above, when at the selectingstep the drive assistance mode is selected, it is possible to establishthe drive assistance mode that is appropriate to the predeterminedassistance selectable area. Therefore, the convenience of the automotivevehicle increases. Also, only when the presence of the automotivevehicle on the assistance selectable area is determined at thedetermining step and, at the selecting step the drive assistance mode isselected, the drive assistance mode appropriate to the assistanceselectable area establishes. Otherwise, a usual drive assistance mode isselected. Therefore, an undesirable release of the drive assistance canbe avoided.

Any combination of at least two constructions, disclosed in the appendedclaims and/or the specification and/or the accompanying drawings shouldbe construed as included within the scope of the present invention. Inparticular, any combination of two or more of the appended claims shouldbe equally construed as included within the scope of the presentinvention.

BRIEF DESCRIPTION OF THE DRAWINGS

In any event, the present invention will become more clearly understoodfrom the following description of preferred embodiments thereof, whentaken in conjunction with the accompanying drawings. However, theembodiments and the drawings are given only for the purpose ofillustration and explanation, and are not to be taken as limiting thescope of the present invention in any way whatsoever, which scope is tobe determined by the appended claims. In the accompanying drawings, likereference numerals are used to denote like parts throughout the severalviews, and:

FIG. 1 is a side view showing a motorcycle, which is one of variousautomotive vehicles designed in accordance with a preferred embodimentof the present invention;

FIG. 2 is a top plan view of the motorcycle shown in FIG. 1;

FIG. 3 is a structural diagram of a control device used in themotorcycle;

FIG. 4 is a block circuit diagram showing a behavior detecting unitwhich is one of electric components used in the motorcycles; and

FIG. 5 is a flow chart showing the sequence of operation of the controldevice.

DESCRIPTION OF PREFERRED EMBODIMENTS

A preferred embodiment of the present invention will now be describedwith particular reference to the accompanying drawings. In describingthe present invention, however, the terms “left” and “right” or similarnotations, that are used hereinabove and hereinafter, are to beunderstood as relative terms descriptive of positions and/or directionas viewed from a driver maneuvering an automotive vehicle whileoccupying the seat during the forward travel of the automotive vehicle.

FIG. 1 illustrates a side view of a motorcycle, which is one of variousautomotive vehicles designed in accordance with the preferred embodimentof the present invention. The motorcycle shown therein includes amotorcycle frame structure FR made up of a front half framesubstructure, including a main frame 1, and a rear half frame structureincluding a rear frame 2 that is connected with a rear portion of themain frame 1. A front fork 4 is supported by a front end of the mainframe 1, and a front wheel 6 is fitted to a lower end of the front fork4. A handlebar 8 and a meter unit 9 are fitted to an upper end of thefront fork 4.

The main frame 1 has a rear end lower portion provided with a swingarmbracket 10. A swingarm 12 has a front end supported by the swingarmbracket 10 for pivotal movement in an up and down direction or in avertical direction. This swingarm 12 has a rear end to which a rearwheel 16 is fitted. A motorcycle combustion engine E is fitted to alower portion of the main frame 1, and is drivingly connected with therear wheel 16 through an endless chain 18 to drive the rear wheel 16.Also, a side stand 19 is supported at a lower end portion of the mainframe 1 at a location on a left side of the motorcycle.

A rider's seat 20 and a fellow passenger's seat 22 are supported by therear frame 2. A fuel tank 24 is fitted to an upper portion of the mainframe 1, that is, at a location between the handlebar 8 and the rider'sseat 20.

A cowling or fairing 26 is supported by a main frame 1 so as to enclosean area forwardly of the handlebar 8 to portions on respective sides ofthe combustion engine E. The cowling 26 has a front end portion on whicha headlight 28 is mounted, and left and right back viewing mirrors 30are fitted to an upper portion of the cowling 26. Also, at a portion ofthe cowling 26 beneath the headlight 28, left and right front turnindicators 32 are fitted.

The rear frame 2 has a tail lamp 34 fitted to a rear end thereof. Aportion of the rear frame 2 beneath the fellow passenger's seat 22 isenclosed by left and right rear cowls 36 externally from lateral sides.Left and right rear turn indicators 38 are mounted on a rear portion ofthe rear cowl 36 and supported by the rear frame 2. A rear flap 40 issupported by a rearward lower portion of the rear frame 2. A numberplate 42 is fitted to the rear flap 40, and a license lamp 44 forilluminating the number plate 42 is fitted to an upper portion of therear flap 40.

As shown in FIG. 2, a mode selector switch 46 for changing a drivingmode (running mode) of the motorcycle is fitted to a left handlebarsegment 8 a of the handlebar 8. This mode selector switch 46 is operableto select one of the driving modes such as, for example, a modeassociated with the output or a mode associated with a traction controlperformance for alleviating an idle rotation of a tire during the startor acceleration of the motorcycle, which driving mode affects themotorcycle operating feeling. The output associated with the outputreferred to above includes, for example, a full power mode and a lowpower mode. A brake lever 48 is fitted to a right handlebar segment 8 b,and a brake pedal 50 is disposed on a right side of the motorcycle at alocation below the rider's seat 20. A main switch 52 for initiating theoperation of the motorcycle is disposed forwardly of the handlebar 8.

The motorcycle according to the present preferred embodiment is aso-called full cowl type in which the front portion of the motorcycle inits entirety is enclosed by the cowling 26, and is suitably used inrunning not only on the public road, but also on the non-public roadarea such as the circuit. The motorcycle according to the presentpreferred embodiment has an antilock brake system ABS mounted thereon,which ABS is one of types of drive assistance device for assisting themaneuvering by the driver.

As shown in FIG. 3, the antilock brake system ABS includes an ABScontrol unit 54, and respective signals from a front wheel speed sensor56 and a rear wheel speed sensor 58 are inputted to the ABS control unit54. Braking maneuvers from the brake lever 48 and the brake pedal 50 aretransmitted respectively to a front wheel brake 60 and a rear wheelbrake 62 through the ABS control unit 54. On the basis of the respectivesignals from the wheel speed sensors 58 and 60, the ABS control unit 54activates each of the brakes 60 and 62 so as to prevent the motorcyclewheels from being locked and then skidding on the road surface duringthe braking operation.

The drive assistance device detects a vehicle condition or a driver'smanipulation and, in the event that a condition that requires a driveassisting control is determined on the basis of the result of such adetection, issues an operation assisting command to a control target.The control target referred to above includes an electronicallycontrollable device which will affects the running feeling. As thecontrol target, a driving device such as, for example, the engine or anelectric motor, a braking device such as the brakes, a cushioning devicesuch as a suspension, steering device, a power transmitting device andso on may be included.

Specifically, the drive assistance device may include, besides theantilock brake system ABS, a traction control (a start assistance deviceand/or a low friction road running support device), an electroniccontrol suspension, CBS (a front and rear wheel cooperation brakesystem), an automatic transmission device, an electronically controlledsteering damper, an idling stop, an output regulation, a wheel speedregulation, a collision originating damage retarding brake or anautomatic operation or the like.

Also, the drive assistance device is preferably of a type in which anelectronically controllable actuator or a sensor is mounted foraccomplishing the drive assistance. This type of actuator may include,for example, an electronically controllable hydraulic unit, which may beused in the antilock brake system or the front and rear wheelcooperation brake system or the like, an electronically controlledsuspension and an electronically controlled steering damper.

The motorcycle employed in the practice of the present preferredembodiment is provided with a determining unit 64 which determines thepresence of the motorcycle on the non-public road area. In the practiceof this embodiment, the determining unit 64 is employed in the form of aprogram loaded in an engine control unit ECU. This determining unit 64is operable to determine the presence on the non-public road area when aprotective appliance for the motorcycle is removed. The protectivedevice referred to above means a statutorily required equipment, whichis one of equipment required when running on the public road area, forthe sake of security and may be, for example, a warning sound horn (notshown), the back viewing mirrors 30, the headlamp 28, turn indicators 32and 38, the tail lamp 34 or the like. The equipment required during therunning on the public road may be, besides the protective devicerefereed above, the number plate 42, the license lamp 44, the side stand19 and so on.

A determining condition 65, under which the determining unit 64determines the presence of the motorcycle on the non-public road area,includes a condition in which at least one of the protective devicesreferred to above is removed. In place of the protective devices,removal of the previously discussed equipment including the protectivedevices may be rendered to be the determining condition 65. In suchcase, removal of two or more of the previously discussed equipment maybe included as the determining condition 65. Thereby, it is possible toavoid the possibility of determining that the motorcycle may be presenton the non-public road area as a result of an erroneous operation. Theremoval of the equipment including the protective devices is detected bya removal detecting unit 66.

In the event that the equipment is employed in the form of an electriccomponent, the removal detecting unit 66 detects removal of theequipment in reference to a detection signal fed from a behaviordetecting unit 68 that is mounted on the motorcycle for the purpose ofdetecting the motion of the electric component. The behavior detectingunit 68 referred to above is operable to detect, for example, the ratioof the “change in electric power consumption/change in electric voltage”of an electric bulb, breakage of the power supply line and/or a sidestand sensor or the like.

FIG. 4 shows one example of the behavior detecting unit 68. Each of theleft and right front turn indicators 32 is provided, besides an electricpower line L1 for respective light emitting elements 32 a, with adetection line L2 for the purpose of removal detection, and the behaviordetecting unit 68 is connected with this detection line L2. A connector67 is interposed on each of the power supply line L1 and the detectionline L2. When with the connectors 67 having been separated the frontturn indicators 32 are removed from the motorcycle, the behaviordetecting unit 68 detects breakage of the power supply line L1 and thedetection line L2 to thereby issue respective detection signals. In thisway, when the detection line L2 is provided separate from the powersupply line L1, it is possible to avoid such an erroneous operation asto detect the breakage of the electric bulbs as removal of the frontturn indicators 32.

Where the equipment shown in FIG. 3 is not an electric component such asthe back viewing mirror 30, the number plate 42 or the like, theprovision is made of a sensor 70 for detecting the removal of suchequipment so that the removal of the equipment can be detected on thebasis of a signal from this sensor 70. The sensor 70 referred to abovemay be employed in the form of, for example, a mechanical contact switchor a reflection type photo-sensor. The determining unit 64 determinesthat the motorcycle is present on the non-public road area when thedetermining condition 65 including the detection signal from the removaldetecting unit 66 is satisfied.

The determining condition 65 referred to above may include, in additionto the detection signal from the removal detecting unit 66 as discussedabove, a condition that the motorcycle is running at a speed not higherthan a predetermined speed or in a running halt condition. Also, thedetermining condition 65 may include the slip ratio descriptive of idlerotation of either of the front and rear wheels, the motorcycle speed,the acceleration degree, the deceleration degree or the like. In otherwords, based on those motorcycle running condition, the motorcycle isdeemed as running on the non-public road area and, hence, the conditiondescriptive of the presence on the non-public road area may be set inthe determining condition 65. Also, the determining condition 65 may bedefined so that during the execution of the assisting control, a modechange may be invalidated. When the determining condition 65 is sodefined as discussed above, the reduction of the running feeling can beavoided. The motorcycle according to the present preferred embodiment isequipped with a selector unit 55 capable of selecting the antilock brakesystem to one of a public road mode M1 and a non-public road mode M2when the presence of the motorcycle on the non-public road area isdetermined by the determining unit 64. So long as the presence on thenon-public road area is not determined, the antilock brake system ABScannot be selected to the non-public road mode M2. In other words, onlywhen the motorcycle is determined as present on the non-public roadarea, the antilock brake system ABS can be selected to the non-publicroad mode M2. The selector unit 55 is so constructed that the driver canmake the selection during a motorcycle run enabled condition. In thepractice of the present preferred embodiment, the selector unit 55 iscomprised of the mode selector switch 46 and a drive control unit 57which is the program contained in the engine control unit ECU.

The motorcycle run enabled condition referred to above is to beunderstood as including a motorcycle halted condition. This motorcyclerun enabled condition is so defined that, before and after theoperation, a motorcycle run disabled condition such as, for example, theremoval of a motorcycle mounted component will not be passed and is, forexample, a condition in which, as a result of the main switch 52(ignition switch) having been manipulated, the electric power supply tothe electric component is permitted is maintained. Also, the selectorunit 55 referred to above is preferably of a structure that can beselected by the driver while the latter is riding. A switch used in anapplication other than the mode selection may be used concurrently withthe selector unit 55.

The mode selector switch 46 includes a plurality of selector switches,and the drive control unit 57 determines the selection of the non-publicroad mode M2 when a plurality of switching manipulations of the modeselector switch 46 are accomplished. In the case where the mode selectorswitch 46 is comprised of a single selector switch, the selection of thenon-public road mode M2 may be determined when the switch is manipulatedfor a period longer than a predetermined length of time.

More specifically, by simultaneously manipulating two switches, whichare provided on left and right sides, respectively, for a period longerthan the predetermined length of time, the mode selecting operation iscarried out. Alternatively, while the condition, in which the mode canbe selected, is attained by manipulating a mode selector button providedin the meter unit 9 or in a handle switch, the selector button may beused to accomplish the mode selection. Any erroneous operation can beavoided by setting such a mode selecting operation that takes place notby a single operation, but through a plurality of steps and/or providinga wait time.

The mode selector switch 46 referred to above may be of any switch thatcan be disposed at a manipulatable position while the driver rides onthe motorcycle, and may be employed in the form of, for example, aselector switch for the driving mode, a selector switch for a meterdisplay mode, or a switch for the running maneuver (for example, aswitch for turn indicators, a switch for horns, a beam high-lowswitching switch for lamps or the like). By concurrently utilizing theexisting switch that can be manipulatable during the riding, the cost ofmanufacture can be reduced with no need to employ any separate switch.

When the non-public road mode M2 is selected, the antilock brake systemABS is disabled. In place thereof, with the non-public road mode M2, theefficacy of the antilock brake system ABS is, for example, lowered.Alternatively, change may be made to allow the antilock decision to beretarded. Again alternatively, when the non-public road mode M2 isselected, the brake operation assistance by means of either one of thehydraulic units for the front and rear wheels may be disabled. Asdiscussed above, during the non-public road mode M2, as compared withthat during the public road mode M1, the drive assistance amount bymeans of the control device is suppressed or disabled. Thereby, amotorcycle behavior appropriate to the driver's operation can beattained. When the non-public road mode M2 is selected, only theantilock brake system ABS for the rear wheel may be dispensed with.

Also, when the non-public road mode M2 is selected, the display throughthe meter unit 9 may be changed for running on the non-public road, or aswitch exclusively for use running on the non-public road may bedisplayed on the meter unit 9. As a display of the meter unit 9 when thenon-public road mode M2 is selected, the display which is counted in thenon-public road area may be given priority. More specifically, theengine rotational number may be displayed in preference to the displayof the motorcycle running speed, or the gear shifting position and/orthe lap time may be displayed emphatically. Also, a selection screenimage may be displayed so that the non-public road mode M2 may beselected. In details, a screen image is displayed which shows a selectorswitch for the non-public road mode M2 that can be selected by means ofmanipulation, and also the selected mode is displayed.

The control device 69 for the motorcycle is constituted including theremoval detecting unit 66, the determining unit 64, the selector unit 55and the drive control unit 57.

The meter unit 9 referred to previously displays, when the determiningunit 64 determines the presence of the motorcycle on the non-public roadarea, such an indication that the public road mode M1 and the non-publicroad area M2 can be selectable. The meter unit 9 further displays, whenthe non-public road mode M2 is selected by the selector unit 55, such anindication that the non-public road mode M2 is being selected.

In other words, in the practice of the present preferred embodiment,when the presence on the non-public road area is determined and theselecting operation is performed by the driver, the drive assistancedevice is changed from the public road mode M1 over to the non-publicroad mode M2. By changing the drive assistance device over to thenon-public road mode M2 through the driver's affirmative mode selectingoperation in the manner described above, the driver can easily recognizethe change of mode.

Even though the assistance performed by the drive assistance device ischanged to the non-public road mode as described above, the motorcyclecan be driven by the maneuver, performed by the driver. The driveassistance device, which enables the selection of the non-public roadmode in the event that the motorcycle is present on the non-public roadarea, is preferably so set that, in the event of the presence of themotorcycle on the public road area, the non-public road mode may beunable to be changed.

The drive assistance device referred to above is preferably operable tocarry out the drive assistance during running on the public road area isobligatory or required at the present or in future years. With the driveassistance device so designed as described above, there is no need topurchase any automotive vehicle, for example, motorcycle dedicated foruse on the non-public road area. Also, since it is possible to run onthe public road area and then to move onto the non-public road area,there is no need to transport the dedicated automotive vehicle to thenon-public road area and, hence, the convenience can be increased. Theantilock brake system ABS employed in the practice of the presentpreferred embodiment may be occasionally required by law when travellingon the public road.

With particular reference to FIG. 5, a vehicle control method with theuse of the control device 69, that is, a drive assistance method of themotorcycle will be described. The drive assistance method according tothe present preferred embodiment includes a removal detecting step S1, adetermining step S2, a first selecting step S3, and a first switchingstep S4 as detailed subsequently.

At an operation start stage S0 in which the main switch 52 is turned on,the public road mode M1 is selected, followed by the removal detectingstep S1. Before the public road mode M1 is changed over to thenon-public road mode M2, the public road mode M1 is sustained.

At the removal detecting step S1, when the removal of the protectivecomponent or the mounted equipment referred to previously is detected,the determining step S2 follows. The removal detecting step S1 issustained by the time the removal of the protective component or themounted equipment is detected removed. At the determining step S2, whenthe determining condition 65 including the detection signal at theremoval detecting step S1 is satisfied, the presence of the motorcycleon the non-public road area is determined and, hence, the non-publicroad mode is allowed to be selectable. If at this determining step S2the determining condition 65 is not satisfied, the process returns tothe removal detecting step S1.

The non-public road mode selectable condition is a condition in whichselection from the public road mode M1 to the non-public road mode M2 ispossible, and is followed by the first selecting step S3. During thenon-public road mode selectable condition, for example, the selectionimage screen descriptive of the selection of the non-public road mode M2is displayed on the meter unit 9 and, at the same time, the switchingoperation to change to the non-public road mode M2 is validated. Inother words, in the event that the non-public road mode selectablecondition is not passed through, the switching operation even ifexecuted is invalidated and no mode change is executed. Immediatelyafter the shift to the non-public road mode selectable condition, thestatus that the public road mode M1 has been selected is displayed onthe meter unit 9.

At the first selecting step S3, if the switching operation to thenon-pubic road mode M2 is carried out by the driver, the process goes tothe first switching step S4. The first selecting step S3 is sustained bythe time the switching operation is carried out.

AT the first switching step S4, in response to the selection of thenon-public road mode M2 during the first selecting step S3, switching ismade to disable the antilock brake system ABS. Other than the selectionof the non-public road mode M2 at the first selecting step S3, theantilock brake system ABS remains under the public road mode M1. At thefirst switching step S4, the switching of the antilock brake system ABSto the non-public road mode M2 is performed, and also the selected modeis displayed on the meter unit 9, followed by a second selecting stepS5.

At the second selecting step S5, when the return operation is carriedout by the driver back to the public road mode M1, the process goes tothe second switching step S6. At the second switching step S6, theantilock brake system ABS is switched to the public road mode M1 and theselected mode is displayed on the meter unit 9. The program subsequentlyreturns to the first selecting step S3.

When at each of the steps S1 to S5 the main switch 52 is switched off, aterminating operation takes place. Therefore, when the main switch 52 isagain switched on, the public road mode M1 is again selected, followedby the removal detecting step S1. In other words, when the motorcyclestarts, it starts from the public road mode M1 by all means.Accordingly, in the event of switching to the non-public road mode M2,each time the starting initiation takes place in the motorcycle, adriver should have an affirmative will to select onto the non-publicroad mode M2. Thereby, even when during the previous run the main switch52 is turned off while the non-public road mode M2 is maintained, it ispossible to avoid resumption of the drive assistance device undesirablyunder the non-public road mode M2.

In the construction hereinabove described, due to the employment of theselector unit 55 shown in FIG. 3, when the driver selects the non-pubicroad mode M2 on the non-public road area, the antilock brake system ABScan be disabled and, therefore, the convenience of the motorcycleincreases. Also, other than the case in which the determining unit 64determines that the motorcycle is present on the non-public road area,the selection of the non-public road mode M2 is impossible and, hence,it is possible to avoid an undesirable release of the antilock brakesystem ABS.

The selector unit 55 referred to above is constituted by the modeselector switch 46 with which the driver can make the selection duringthe motorcycle run enabled condition. Accordingly, with no need todismantle the motorcycle, the non-public road mode M2 can be easilyselected and, therefore, the convenience can be increased.

Also, the selector unit 55 selects the antilock brake system ABS to thepublic road mode M1, when the main switch 52 for starting the motorcycleis operated. Therefore, even though the drive operation is previouslyterminated under the condition of the non-public road mode M2, thepublic road mode M1 is started when the next drive reopening takeplaces. For this reason, it is possible to avoid the antilock brakesystem ABS from being disabled when the motorcycle runs on the publicroad.

When the determining unit 64 determines that the motorcycle exists onthe non-public road area, the meter unit 9 displays an indication thatselection of the public road mode M1 and the non-public road mode M2 canbe selectable, and, also, displays, in the event of the selection of thenon-public road mode M2, an indication that the non-public road mode M2is now selected. Accordingly, that the non-public road mode M2 isselectable can be affirmed with naked eyes and, therefore, theconvenience is increased further, and also the driver can be arousedthat the motorcycle is now under the non-public road mode M2.

During the run on the public road, by the operation of the mode selectorswitch 46 for selecting the driving mode (running mode), the drivecontrol unit 57 determines the selection of the non-public road mode M2.Therefore, no use of any extra switch is needed for the selector unit55.

The drive control unit 57 referred to above determines the selection ofthe non-public road mode M2 when the plurality of switching operationsare performed. Therefore, it is possible to avoid the selection of thenon-public road mode M2 by means of an erroneous operation of thedriver.

The determining unit 64, when the protective component of the motorcycleor the equipment (including the protective component) is removed,determines the non-public road area. As such, the presence on thenon-public road area can be determined when the protective component orthe equipment (including the protective component) necessary whenrunning on the public road area but unnecessary when running on thenon-public road area is removed. Therefore, the motorcycle can bechanged to that for use on the non-public road without any specialoperation being performed. More specifically, during the run on thenon-public road the antilock brake system can be disabled. Thereby, theconvenience is further increased.

In the case where the protective component (equipment) is an electriccomponent, the removal detecting unit 66 detects the removal of theequipment from a detection signal, fed from the behavior detecting unit68 mounted on the motorcycle for detecting the behavior of the electriccomponent. Accordingly, there is no need to use any extra sensor thatfunctions as the removal detecting unit 66 and an undesirable increaseof the number of component parts can be suppressed. Where the equipmentis not the electric component, the removal of the equipment can bedetected by a signal fed from the sensor 70 for detecting the removal ofthe equipment.

As a control device 69A designed in accordance with a first modificationof the control device 69 discussed hereinbefore, provided is a secondnon-public road area detecting unit 72 for detecting the presence of themotorcycle on the non-public road area besides the removal of thecomponent, and the determining condition 65A includes a detection signalfed from the second non-public road area detecting unit 72. This secondnon-road area detecting unit 72 is a device capable of determining thepresence of the motorcycle in the non-public road area with the use ofboth of a unit for detecting the current position of the motorcycle suchas GPS and a geographic information stored beforehand. Transmission of asignal from the non-public road area detecting unit 72 may beaccomplished by either wire or wireless.

According to the above described first modification, by the use of thetwo signals, one from the removal detecting unit 66 and the other fromthe non-public road detecting unit 72, as the determining condition 65A,any erroneous detection can be avoided.

As a control device 69B designed in accordance with a secondmodification of the control device 69 discussed hereinbefore, in placeof the second non-public road detecting unit 72 or in addition to thesecond non-public road detecting unit 72, included is a mount detectingunit 74 for detecting that a component which is utilized by themotorcycle only on the non-public road area, and a determining condition65B includes a detection signal fed from this mount detecting unit 74.The component that is utilized only on the non-public road areaincludes, for example, a control unit for the circuit, a circuitcertificate key, a competitor's number plate or the like. The mountdetecting unit 74 outputs a signal indicative of the non-public roadarea when the engine control unit ECU is replaced with the control unitfor the circuit or when an identification key is inserted into a keyswitch unit.

According to the above described second modification, with the use ofboth of the signal from the removal detecting unit 66 and the signalfrom the mount detecting unit 74 as the determining conditions 65B, itis possible to prevent, as a result of an erroneous detection, fromchanging the motorcycle to the non-public mode.

Although the present invention has been fully described in connectionwith the preferred embodiments thereof with reference to theaccompanying drawings which are used only for the purpose ofillustration, those skilled in the art will readily conceive numerouschanges and modifications within the framework of obviousness upon thereading of the specification herein presented of the present invention.By way of example, although in describing the preferred embodiment ofthe present invention as set forth above, reference has been made to theuse of the antilock brake system as the drive assistance device, thepresent invention is not necessarily limited thereto and is generallyapplicable to any control in which maneuver interposition control in anyway is generated to the maneuver performed by the driver. Specifically,the drive assistance device may be a traction control which is effectiveto avoid an idle rotation of the tire during the start and acceleration,an electronic control suspension, an output regulation or the like. Thedrive assistance device is so constructed as to suppress the maneuverinterposition during the non-public road mode as compared with thatduring the public road mode.

When the non-public road mode is selected, light emitting componentssuch as, for example, the turn indicator 32 and 38, the brake lamp 34,position lamps and so on may not be lit. By so doing, when themotorcycle runs erroneously on the public road while selecting thenon-public road mode, the driver can be reminded to such error.

Also, although in describing the preferred embodiment of the presentinvention as set forth above, the use has been shown and described asthe detecting line L2 separate from the power supply line L1 shown inFIG. 4, with the behavior detecting unit 68 connected with those linesL1 and L2. However, without the use of the detecting line L2, only thepower supply line L1 may be connected with the behavior detecting unit68. Although in the foregoing embodiment described hereinbefore, thedetermining unit 64 and the selector unit 55 have been shown anddescribed as contained in the engine control unit ECU, the presentinvention is not necessarily limited to that and they may be containedin, for example, the meter unit 9.

Again, although in describing the preferred embodiment of the presentinvention as set forth above, the public road mode M1 has been describedas selected when the main switch 52 is turned on, such an arrangementmay be satisfactory that at the time of the operation start to drive theengine E from a halted condition the public road mode M1 is selected.For example, in the event that decision is made of run completion at thetime the main switch 52 is turned off or the like, storage is made toallow the public road mode M1 to be stored as a mode assumed at thesubsequent operation start. Also, arrangement may be made that duringthe period in which the engine E is rotating, the selected mode may besustained. Furthermore, when a predetermined time elapses during whichthe run halted condition continues after the non-public road mode M2 hasbeen selected by the selector unit 55, the public road mode M1 may beresumed.

The structure may be so configured that the non-public road mode M2 maybe selected from one of a plurality of options, not from one stage thateliminate the use of the drive assistance. More specifically, forexample, a plurality of modes having varying degrees of drive assistanceis prepared, one of the plurality of options may be selected by theselection done by the driver. By so doing, on that particular occasionof the non-public road area, the drive assistance preferred by thedriver can be selected.

Although in describing the preferred embodiment of the present inventionas set forth above, reference has been made to the determination of themotorcycle on the non-public road area, but arrangement may be made thatonly when detecting the presence of the motorcycle on the area for whichthe predetermined mode can be selected, the driver can select the modeof the drive assistance device. In such case, effects brought about bythe above described embodiment can be attained even on the public roadand in the area that is exceptionally treated as the non-public road.Further, the selection of the driving mode may be invalidated duringrunning on either of a freeway or a general road. Also, of the publicroad, where the area (country, area) in which the installation of thedrive assistance device is compulsory exist, arrangement may be madethat the mode of the drive assistance device can be selected in the areaexcluding such area.

Although in describing the preferred embodiment of the present inventionas set forth above, the case has been discussed in which the mode of thedrive assistance device can be selected only when the presence of themotorcycle on the non-public road area is determined, a reverseoperation may be done. In other words, in the event of the presence ofthe motorcycle in the area in which the installation of the driveassistance device is compulsory is determined, the selection of the modeof the drive assistance device is invalidated or disabled and the mode(public road mode) of a predetermined drive assistance device may beexecuted.

While in the practice of the preferred embodiment of the presentinvention, it has been described that the driver riding on themotorcycle can select the mode of the drive assistance device,arrangement may be made that the driver in an exited condition canselect it. Specifically, for example, a mode changing switch may be heldwithin a ditty bag or provided underneath the seat. Accordingly, whenchanging the mode, it is possible to avoid the driver from conducting amode switching operation undesirably.

Where a device capable of detecting the position of the motorcycle suchas, for example GPS is mounted, the presence of the motorcycle on thenon-public road area may be determined with the use of such device.Also, the non-public road area may be determined by storing thenon-public road code, which is a descriptive of the non-public roadarea, in advance and comparing the stored non-public road code with acode fed from the outside of the motorcycle. Such non-public road codemay be encrypted or may be received through wire or wireless.

A switch portion of the selector unit 55 may not be necessarily limitedto the mode selector switch 46, and may be a switch provided in, forexample, the meter unit 9. In describing the preferred embodiment of thepresent invention as set forth above, reference has been made to themotorcycle, but the present invention can be equally applied to anyautomotive vehicle other than the motorcycle.

Accordingly, such changes and modifications are, unless they depart fromthe scope of the present invention as delivered from the claims annexedhereto, to be construed as included therein.

REFERENCE NUMERALS

-   -   9 . . . Meter unit (Display unit)    -   28 . . . Headlamp (Protective component)    -   30 . . . Back viewing mirror (Protective component)    -   32 . . . Front turn indicator (Protective component)    -   34 . . . Tail lamp (Protective component)    -   38 . . . Rear turn indicator (Protective component)    -   46 . . . Mode selector switch    -   52 . . . Main switch    -   55 . . . Selector unit    -   64 . . . Determining unit    -   S2 . . . Determining step    -   S3 . . . Selecting step    -   S4 . . . Switching step    -   ABS . . . Antilock brake system (Drive assistance device)

What is claimed is:
 1. An automotive vehicle which comprises: adetermining unit to determine the presence of the automotive vehicle ona non-public road area; a drive assistance device to assist a drivingoperation of a driver; and a selector unit to select a drive assistanceby the drive assistance device from a public road mode to a non-publicroad mode in the event that the determining unit determines the presenceof the automotive vehicle on the non-public road area, wherein theselector unit is configured as to be selectable by the driver in avehicle run enabled condition.
 2. The automotive vehicle as claimed inclaim 1, the selector unit is prohibited from selecting the mode of thedrive assistance when running on the public road area.
 3. The automotivevehicle as claimed in claim 1, in which the selector unit selects thedrive assistance device to the public road mode at an operation startstage at which a vehicle operation is initiated.
 4. The automotivevehicle as claimed in claim 1, further comprising a display unit todisplay the capability of selecting the public road mode and thenon-public road mode in the event that the determining unit determinesthe automotive vehicle present on the non-public road area and also todisplay the non-public road mode being selected in the event that thenon-public road mode is selected.
 5. The automotive vehicle as claimedin claim 1, further comprising a mode changing switch to select adriving mode during the run on the public road, wherein the selectorunit determines the selection of the non-public road mode when the modechange switch is operated.
 6. The automotive vehicle as claimed in claim1, wherein: when the determining unit determines the presence of theautomotive vehicle on the non-public road area, the selector unitenables the selection of the non-public road mode while the public roadmode is maintained; and when the selector unit selects the non-publicroad mode, the mode of the drive assistance device is changed to thenon-public road mode.
 7. The automotive vehicle as claimed in claim 1,in which the determining unit determines the non-public road mode when aprotective component of the automotive vehicle is removed.
 8. Theautomotive vehicle as claimed in claim 1, further comprising a mountdetecting unit configure to output a signal indicative of the non-publicroad area when an identification key is inserted into a vehicle body,wherein the determining unit determines the presence of the automotivevehicle on the non-public road area based on the signal from the mountdetecting unit.
 9. The automotive vehicle as claimed in claim 1, whereinthe selector unit selects the mode of the drive assistance device intothe public road mode when a predetermined time elapses during which therun halted condition continues after the non-public road mode has beenselected.
 10. A drive assistance method for use in an automotive vehiclethat is equipped with a drive assistance device for assisting a driveoperation performed by a driver, which method comprises: a determiningstep to determine the presence of the automotive vehicle on apredetermined assistance selectable area by a determining device; aselecting step to enable a drive assistance mode by the drive assistancedevice by the driver only when the presence of the automotive vehicle onthe assistance selectable area is determined by the determining step;and a switching step to change to the drive assistance mode, selected bythe selecting step, to enable the drive assistance to be accomplished.